1. Field of the Invention
The present invention relates to a pedal switch assembly operatively associated with an operating pedal for an automobile, such as a clutch pedal and a brake pedal.
2. Description of the Prior Art
There is a conventionally known pedal switch assembly in which as a pedal is depressed down, a change-over signal is produced which is indicative of command to change over each of a plurality of control devices used in an automobile, e.g., a constant speed travel control device, an air-fuel ratio correction control device, an antilock brake control device, and a four wheel drive (4WD) to two wheel drive (2WD) change-over device to a selected operation state of that device.
The plurality of control devices are different in function and purpose of use from one another and hence, the optimal timings for changing over the states of operation of the control devices on depression of the pedal may be different from one another. For example, with the constant speed travel control device, the operation thereof is desired to be released substantially in concurrence with clutching of an operator or driver and for this reason, it is desirable that even with a slight amount of clutch pedal depressed, a change-over signal is produced from the pedal switch assembly. On the other hand, with a control device for controlling the air-fuel ratio of an engine for correction, or controlling the supply of a fuel during a speed-reducing operation, the operation thereof is desired to be released after the clutch is brought into a completely disengaged state and for this reason, it is desirable that a change-over signal is produced from the pedal switch assembly after the amount of clutch release reaches a sufficient large value.
However, the above prior art pedal switch assembly is constructed to simultaneously produce the change-over signals to all of the plurality of control devices when the amount of pedal depressed has exceeded a predetermined value and therefore, it is accompanied by a problem that one or more of the control devices may be released in operation at too early or too late of a timing. When the timing for producing the change-over signal from the pedal switch assembly is set a little early for optimal timing for example, when the operation of the constant speed travel control device is released, mere light placement of an operator's foot onto the clutch pedal (many persons drive with their feet remaining lightly placed on the clutch pedal in this way during normal operation) causes the operation of not only the constant speed travel control device but also the air-fuel ratio correction control device and other devices to be simultaneously released and consequently the air-fuel ratio correction control device and other devices will not effectively function in spite of the fact the clutch is not disengaged yet.